Rear Suspension Shock Absorber problems of the 2014 Chevrolet Silverado

The vehicle has an established, measureable and documented vibration problem that randomly increases & decreases in applitude & frequency at all speeds. Gm is unable to resolve after 12 dealer attempts to address, including multiple sets of tires, rear differential, drive shafts and shock absorbers all failing to resolve the issue. Gm stated vibration is inherent to the design and no further action needed or will be taken ever for vibration, regardless of circumstance. Such a vibration is a significant safety defect because it is essentially like cutting wires to warning tell-tales by removing a driver's ability to discern tire/suspension/powertrain/steering problems that can only be identified by feeling a vibration (such as a loose wheel or damaged suspsension components) prior to a catastrophic event, especially at high speeds. Not only for the vehicle occupants, but also for any road user when it results in the driver loosing control of the vehicle. Gm's own attempts to fix the vehicle with the list of parts above irrefutably supports the inability for a driver to identify the source of a vibration. If experienced technicians and subsequent corporate engineers cannot recognize the vibration as being different from wheels, suspension, powertrain; then a normal driver will have no such warnings available should a potentially catastrophic safety issue be present. Further, since gm refuses to address any further vibration issues with this vehcile, it is like have a airbag warning tell-tale continuously illuminated whether or not a problem exists & gm stating to just live with it. In other words, if I get a loose wheel, I guess gm figures I will know it when it falls off. In addition, to safety defect described above, the vibration is an extreme source of driver distraction & driver rage as attempts are made to produce and/or reduce the vibration while driving.